This invention relates to conveyor chain links and, more particularly, to chain links adapted for use with a fingered transfer plate.
Typically, when a flat plate chain is used in conjunction with a transfer plate, there is a gap between the chain and the transfer plate. This gap may cause articles being carried on the top surface of the chain to tip or hang up at the point of transfer. A fingered transfer plate has been used in the past as a solution to this problem. U.S. Pat. No. 4,051,949, hereby incorporated by reference, hereinafter referred to as the Lapeyre patent, illustrates a conveyor system using such a fingered transfer plate. The Lapeyre patent refers to problems with this type of chain, such as kick-up due to the chordal effect, and provides methods for minimizing some of the problems. There are, however, several other problems with this type of chain which the Lapeyre patent does not address.
For example, it is desirable to make this type of chain so that it may be driven by a sprocket having fairly wide teeth for handling large loads. At the same time, while it is necessary that there be discontinuities along the width of the top surface of the chain so that the chain may mesh with a fingered transfer plate, it is important that those discontinuities not be large enough to permit the articles being carried on the chain to tip over. The links shown in the Lapeyre patent seem to be meant to form a belt which would be driven by a drum, rather than a chain to be driven by sprockets, but it is clear that if a sprocket were to be used with the Lapeyre type of chain, the sprocket teeth could never be wider than the width of the discontinuities in the top surface of the chain. Thus, in order to use a wide-toothed sprocket with the links shown in the Lapeyre patent, it would also be necessary to have wide discontinuities in the top surface of the chain.
One object of the present invention is to provide a chain which may be used with a fingered transfer plate. Another object is to provide a chain having barrels which may be driven by sprocket teeth. Another object of the present invention is to provide a chain with sufficient strength to withstand substantial loads. Another object of the present invention is to provide a chain which has the capability of back-flexing. Another object of the present invention is to provide a chain with sufficient open area for drainage and air flow through the chain. These and other objects will be apparent to one skilled in the art upon reading the Description of the Preferred Embodiments.